Ldap authentications failing for 2 users - Isilon

Hello,

We are currently using Open LDAP for user authentication, It's all working fine till last week, since where we were started complaining about authentication failure for application ID through REST API calls to Isilon cluster. 

All calls are getting timed out.

I verified couple of more LDAP users by loggin into the cluster through SSIP, Dynamic zone name, Static Zone name and individual IP addresses of all nodes. Out of 7 users attempts, I observed, 2 LDAP users are getting timeout responses while loggin to the cluster. One is application ID use for REST API calls, and another is LDAP ID. Remaining all users attempts are successfull in all ways of login.

For these 2 ID's getting time out errors,

1) Login in to node 1 with IP address attempt is successful with spontaneous login response.

2) Login to other nodes with IP addresses are getting time outs with error message server unexpectly disconnected messages

3) Login to cluster using SSIP, dynamic pool address and Static pool address (DNS) is getting time out errors.

Login to other nodes using IP address have 75 Percent of failures and only 25 percent success rate.

We use application ID for provisioning purpose, so due to this unknown issue, we are unable to process our provisioning using automation.

At this time, we are unsure where the issue is located and fix the issue.

On Isilon cluster, login to node 1 with IP address is successfull for all the users but not to the other nodes

Except these 2 LDAP id's, all other ids' are able to login in all means. no issues at all

On LDAP side, only 2 id's are failining.

As per the information, no changes performed on both sides.

We have opened a SR with Isilon and working towards the resolution.  But  any one experienced similar issue ?

Any suggestions would be appreciated.

Thanks,

Hari